Implementing electronic circuits involves connecting isolated devices or circuit components through specific electronic paths. In silicon integrated circuit (IC) fabrication, circuit components that are formed in a single substrate are often isolated from one another. The individual circuit components can be subsequently interconnected to create a specific circuit configuration.
The integrated circuit industry continues to progress in electronic circuit densification and miniaturization. This progress has resulted in increasingly compact and efficient semiconductor devices, which in turn enable the systems into which these devices are incorporated to be made smaller and less power consumptive.
During the formation of semiconductor devices, such as dynamic random access memories (DRAMs), static random access memories (SRAMs), microprocessors, etc., insulating layers, such as silicon dioxide, phosphorous doped silicon dioxide, or other materials, can be used to electrically separate conductive layers, such as doped polycrystalline silicon, doped silicon, aluminum, refractory metal silicides, and layers formed from other conductive materials.
In fabricating electronic circuits, layers of material are applied over each other to provide various features to the circuits. During this process portions or entire layers can be removed in order for layer underneath to be accessed. In some fabrication methods, additional materials can be used to fill in the removed portions. Such layering and removing processes can include, deposition, etching, planarizing, photolithography, among other processes.
In many devices, conductive layers can be interconnected through openings in the insulating layer. Such openings are commonly referred to as contact openings (e.g., when the opening extends through an insulating layer to an active device area). Generally, such openings are also referred to as holes or vias (i.e., when the opening extends through an insulating layer between two conductive layers).
In addition to size, the time it takes and material used in a manufacturing process can be important factors in circuit design. For example, aspects that can be changed that can benefit the manufacturing process include the number of layering processes, the time taken to perform the processes, and/or the amount of materials used in these processes can be reduced.